Pre-war valve spring covers.

[Tony Fearn]

I knew it would happen one day, and yesterday was the day. Basking in glorious sunshine here in the premier county of England, with the temperature around 76F and the cherry tree in full blossom next to the motor house, I had been, since early morning, checking over "Mary Ellen" prior to the Centenary Rally on't other side of the Pennine chain in Yorkshire. All seems ok so far, but because of the unleaded petrol story and the dreaded valve-seat recession I thought I'd better check the tappet clearances. No problem with the off side, where everything was hunky-dory but when I came to try to remove the near-side valve spring covers, the beautifully-crafted retaining bolt just went round and round and round and round and round and round ad inf. Obviously the once-captive screwed bit in the lower half has come loose so the bolt won't unscrew, the whole lot just goes round and round etc etc. Hence I will not be able to check the clearances on this side at the moment. But sometime in the near future, I will really need to remove the covers to check things, and this is why I have posted this request. Has it ever happened to you, and if so, how did you manage to undo the bolt and take off the covers? There's not enough room to get an angle grinder at it, and I'm loath to use a cold chisel and a lump hammer. For goodness sake don't say remove the engine from the car!! I'm open to all suggestions and ask for help in all languages translatable in Altavista Babelfish. Regards, Tony.

[PAUL BEAUMONT]

Tony, I am not familiar with the tappet covers on the 7hp, but I have several comments to make - none of them particularly useful, but I have nothing useful to do at this moment - lunch time at work!
1. Angle grinders and lump hammers are for modern tinware not Jowetts!
2. With a compression ratio of a little over 1:1 I suspect that you will never suffer from valve seat recession
3. Wasn't Jowett engineering development wonderful. They must have sussed out this problem by the time they made the Bradford, cause here they used little aluminium half tubes held together by the weakest special bolts you could devise. These twist off with boring regularity, but anticipating the demise of leaded prune juice, they fail in such a way that you can get at the tappets if you feel you must.
4 From my Bradford hand book" whilst it is going well leave the thing alone!"

[Tony Fearn]

Thanks for the reply Paul. I also stand by the axiom -"if it ain't broke don't try to fix it". I just hope that I don't have to lurch every alternate firing stroke over the hills to the White Rose County. Got the Jowetteer today. Excitement and anticipation are growing, and we can't wait to attend the Centenary Rally. Cheers, Tony.

P.S. Having read what I wrote originally about this subject, it's obvious that I was waxing lyrical, although the question was in the body of the posting. Perhaps "Can't get my valve cover off, what do you suggest" might elicit more response, rather than the reader getting bored with irrelevances.

[Tony Fearn]

Hello Pat. No, the earlier pre-war covers are pressed steel. There's a top and a bottom cover on each side. If you put a top and bottom together it will look like a pair of mini binoculars minus the lenses. The bolt is central and passes through the top part of the cover and screws into a captive threaded "nut" on the bottom part. This "nut" doesn't have a hexagonal edge, its edge is round, so that if it becomes loose in the bottom cover plate there's no way of stopping it turning. This means of course that the bolt and the once-captive threaded bit just go round and round. Tony.

[ian Howell]

Tony: - If it is any help - try CAREFULLY drilling the head off the screw from the top. If you remove JUST the head, you could use the 'stump' to get a grip on with grips once the covers are off.

Then of course you will need to 'recaptivate' the nut, but hey . . .

Hope this might be of some help.

[Tony Fearn]

Hi Ian. Thanks for the suggestion. The dynamo is in the way for a straight attack on the head by drill bit, but there may be room if I use a longer bit at an angle. I've just thought, whilst sat here replying, that a flexible shaft on a drill with a mini grindstone on the end might also work. Can't do anything for a week though, as we're off on hol to Provence to rest and relax before the rigours of the National!! This being so, if anyone else is kind enough to reply with a suggestion, I won't be able to respond before the weekend. Regards, Tony.

[Tony Fearn]

Nice one Pat. Thanks. That just might work. Will try it next week before I resort to more complicated or brute-strength methods. Tony.

[Tony Fearn]

Just registering a successful conclusion and thanks. The valve covers are now off the offending side and on checking the tappet clearances, they are both at 2 thou as they should be (according to the manual). So, thanks to all who took the time to suggest remedies:- To Paul, for his "none particularly usefull" ideas - only joking and quoting Paul!, To Ian whose suggestion led me to try a couple of 3/8" extension bars and a ratchet, which can be applied down the side of the dynamo, and to Pat for the idea of pressurising the lower screwed bit with a screwdriver. I'm going to Classic Car Maintenance nightschool tomorrow night so I'll get out the brazing torch. Regards, Tony

[Tony Fearn]

Pat,

I know this reply should have been sent a year ago!! - so sorry for the delay.

From the Pitman's 'Book of the Jowett' it says that the valve clearances should be set as follows:-

1930 models -- four thou for both inlet and exhaust.

1931 models -- four thou exhaust, two thou inlet.

1933 models -- two thou inlet and exhaust.

Other models - just clear for running conditions.

I set "Mary Ellen's valves to two thou. - 1934 short saloon.